Rotary beater and discharge structure therefor for reducing sticky materials



NOV. 9, 1954 KQVAC 2,693,915

ROTARY BEATER AND DISCHARGE STRUCTURE THEREFOR FOR REDUCING STI MATERIALS Filed Dec. 1951 CKY 24,

A 'oRNEX United States Patent ROTARY BEATER AND DISCHARGE STRUCTURE THEREFOR FGR REDUCING-STICKY MATERIALS George M. Kovac, Lincolnwood, Ill., assignorto The W. J. Fitzpatrick Company, Chicago, 111., a corporation of Illinois ducing various types of foodmaterials having a relatively large moisture or oil content to fine partlcles.

In reducing materials by grinding vor comminuting no difliculty is encountered with materials having less than about per cent liquid contentor, more than 50 per cent liquid content. With material whose liquid content is between 15 to 50 per cent, a great deal of difliculty is encountered since. they are neither dry enough nor wet enough to pass through conventional types of reducing equipment, and tend to cling to the parts to build up cakes to blind screens, and in other ways to prevent satisfactory and continuous machine operation. Materials containing oils of various types as their liquid content are more diflicult to handle than those whose liquid content is made up of Water- Such materials are common in the food industry and examples thereof include nutmeg, mace, poppy seed, cheese of various types, vitamin supplements, and similar food products.

It is accordingly one of the objects of the present invention to provide an apparatus for reducing moist material in which moist or oily food materials can be reduced to the desired extent without caking, blinding of screens or otherwise clogging the apparatus in a continuous operation.

Another object is to provide an apparatus for reducing moist material in which the material is'reduced by impact type blades, and is discharged through a relatively large outlet opening designed and positioned to eliminate clogging or caking.

According to one feature of the invention, the outlet opening is a rectangular opening in the lower cylindrical wall of the casing extending the full axial length of the casing and positioned in advance of the center thereof relative to the direction of rotation of the rotor.

Still another object is to provide an apparatus for reducing moist material in which bafiles are provided to direct the reduced material smoothly from the apparatus with no opportunity for clogging or caking.

According to another feature of the invention the baflle at the trailing edge of the opening lies substantially tangent to the chamber wall to pick up the material smoothly and direct it away from the apparatus.

The above and other objects and features of the invention will be more readily apparent from the following description when read in connection with the accompanying drawing in which:

Figure 1 is a partial transverse section through a reducing apparatus embodying the invention, and

Figure 2 is a partial perspective view of the lower casing wall member and baffles.

The apparatus as shown is broadly of the hammer mill type including a cylindrical casing having a rotor therein with radially projecting blades on the rotor. The rotor as shown, comprises a cylindrical hub 10 which is mounted on a rotatable shaft 11 externally driven by an electric motor or other suitable drive means. At spaced points in its periphery the hub 10 is formed with notches 12 into which the inner ends of blades 13 extend. The blades 13 are pivotally connected to the hub by pins 14 extending through the notched portions of the hub and through openings in the inner ends of the blades. The blades 13 may be shaped in any desired manner to present either dull or sharpened edges to the material and any desired number of blades may be employed depending upon the size of the machine.

The rotor is enclosed atiits upper part by an-upper cylindrical casing member 15which-is.provided-atrits top portion with an inlet opening 16. The opening '16 preferably extends at an angle to a radius through itand angles in the direction ofrotation of the rotor-i as :indi-.

cated by the arrow 17 although this is not essential. The upper casing part 15 maybe secured to a mounting framework 18 whichcarries fixed skirt portions 19 extending downward to lower mounting-strips 21 as shown.

The inner surface of .the casmg'portion-15 preferably.

extends relatively close to the tips of the blades =13.

' The casing is completed by a lower plate member 22 which may be detachably supported in-the'frame and which provides a cylindrical surface lying adjacent to the outer ends of the blades 13. The casing-member 22 may be inserted in guide tracks in the endwalls of the casing for easy insertion and removal as more particularly described in the patent'to Magnus No.:2,348,916. When so mounted the lower casing part-22 forms a substantial continuation of the upper'casing part 15 to define a cylindrical chamber inwhich the rotor lies.

' According to the present invention, the lowercasing part .22 is formed with a rectangular outlet opening 23 extending the full axial length thereof. As best seen in Figure 2, the lower casing'part may be formed by a pair of arcuatestrips connected by relatively narrow edge strips- 24 to define the rectangular outlet opening 23. The

opening 23, lies in advance of a vertical plane through the rotor axis relative to the direction oftherotation of the rotor as best seen in Figure 1. Thus the trailing edge of the outlet opening as indicated at 25, lies closely adjacent to and preferably-slightlyin advance of the vertical'center plane. The leadingedge of the opening as indicated at 26, is spaced in advance of the trailing edge 25. The exact width of the opening depends upon the type of material being ground and the fineness of the particle size desired, and is preferably varied by design by changing the spacing between the leading and trailing edges of the opening while maintaining the trailing edge in substantially the position shown.

The spaces between the frame side parts 19 and the casing wall part 22 are preferably closed by bafiles to prevent the reduced material from entering the space between these parts where it might pack or clog. As shown, a straight bafile 27 is secured to the left-hand frame bar 21 and extends upward therefrom to engage the casing wall part 22 closely adjacent to the leading edge 26 of the otulet opening. At the trailing side a curved bafile 28 is provided anchored at its lower end to the right-hand frame bar 21 and curving upward to terminate near the trailing edge 25 of the outlet opening. At its upper edge where it contacts the wall portion 22 the bafile 28 preferably lies substantially tangent to the wall portion and closely adjacent to the trailing edge 25 of the outlet opening.

In use, material to be reduced such as nutmeg, mace, poppy seed, cheese or the like, is fed into the inlet opening with the rotor turning in the direction of the arrow 17. As the material enters the chamber it is struck by the blades 13 which are preferably traveling at a relatively high speed on the order of about 7200 R. P. M. In this way, the blades break up the material into fine particles and carry the particles around the interior of the casing until they are discharged through the opening 23.

As the particles leave the opening 23 they are traveling at a relatively high velocity in a general tangential direction and are picked up by the bafile 28 and directed smoothly away from the apparatus into any suitable container provided therefor.

The bafiie in this way direct all of the reduced particles away from the apparatus without offering an opportunity for particles to collect and build up into cakes or the like, and without requiring any fine screen-like members which could readily become blinded.

The size of the opening 23 is varied in accordance with the material to be reduced and the fineness desired. It has been found, for example, that in reducmg material such as nutmeg and mace, an opening having a circumferential length between 4 and 4% inches produces highly satisfactory results whereas with poppy Patented. Nov. 9, 1954 se'ecf, theopenihgishn the order of 1 inch in length. It has further been foundwith a" machine constructed according to the invention,' that nutmeg can be reduced at the rate of 300 to 400 pounds per hour whereas the maximum production" with conventional type nia- 5 chines-was abomeopountls er hour.

For many: materials of this tyne it is preferable to screen the particles after passing from the machine a'lid toreturn" the larger particles for a' 'e cend rindin op eration especially where a very nhifo'rni product is (16 w sired.- In the production of nutmegfor example; terial was'ruri'thrott'gh the rha'ehine at the ra'te of about 600ponnds p'er hoiir' and'a'ft'ersc'reening and-returnifigthe taili'ngsto tpe maehineg abotit 400 pounds per hour of properly'reduced nutmeg was'obtaitledi; Similar re' suits are obtained with other materials and by selectin the proper; size' of discharge ofieiiing' substantially any of the relativ ly moisten oily msterials; which are din ficultto re'du'cegcan be handled effectively alicl'with a" relatively high-prdduetion rateb 20 What is claimed is: I

1l'AppaIiitl1S f 6f reducing sticky niaitei'iils c'onipris-' ing a-- substantially cylindrical clialnb'er having: 225 inletformaterial to be reduced?iii it's' up1 ""r extendingaxiany threngh'the cnanfie o orrthe rotor projecting radially" the'refr'ofii to terminate adjacent toth cylindrical wall of the chamber;- a arm ar'cuate plate formed=-witli' an' outlet opeiiiiig for r'e'diiced material ih the lower eylindi'ia'lyifzxll 65 the chalribeix'r the on'tlet opening ex te'iidirig suests'igtiany me flill axia 35 length of the chamber" and lyiiig Wholly advance ea a vertical' a xiall p'la'iie" tlirongl? are chainber relative ti) 4. the direction of rotation of the rotor, and a battle extending generally tangentially outwardfromand' engaging the arcuate plate along an axial line adjacent to the edge of the outlet opening at the trailing side thereof relative to the direction of rotation of the rotor the arcuate plate defining a narrowetrailing edge for the olutlet opening lying closely adjacent to said vertical P 51353 a 4 2. Kppa'ratusi for reducingsticky materials comprising a substantially cylindrical chamber having an inlet for Iiiaterial to be redhcd in its-upper portion} a rotor extending-axially througli' the chamb'e'ga series of blades on the rotor projecting radially therefrom to' terminate adjacent to the cylindrical wall of the chamber, a t h in arcuate' plate fo'rhied- Withan diitl'e't opening for reduced material in the lower cylindrical wall of the chamber, the outlet opening extending substantially'the full axial length of the chamber and lying wholly in advance of a vertical-axial" plane through the chamber relative" to the direetionof rotation of the rotor,= and baflles extendi'ri'g' outward frond the leatling and trailing sides of v the outlet openihgi the" bafile at-the trailing side lying substantially: tangent t6 and engaging the ar'cuat'e plate along an axial lineadjaceiitftdthe'trailing side to leave a narrow edge" at the trailing'side'at the openin'g'lying closely adjacent to saldvertical axial plane.

References cite-am the meet this patent UNI'EED STATE PATENTS 

